School children are taught about how the earth is round and orbits around the sun and about the earth's declination on the orbit and how this results in the four seasons. Yet when one goes outside, the earth looks flat and the sun is somewhere in the sky, and it is difficult to fully grasp or appreciate the geometry involved. In addition, modern air travel has greatly shortened the time and effort required to travel great distances around the globe. One crosses multiple time zones, experiences jet lag and may experience different climates or reversal of the seasons upon travel to the opposite hemisphere. Yet the geometry behind this can remain somewhat obscure and theoretical.
Thus, there is a need for a portable device that can be easily carried on trips to enhance the appreciation of the concepts of latitude and longitude, and timekeeping and how these concepts relate to the daily and annual movements of the sun and the stars.